1. The Field of the Invention
This invention relates to structurally strengthened thermoplastics.
2. The Relevant Technology
Wood has long been a favorite building material. Wood is also commonly used in the manufacture of products such as decorative moldings and frames and window coverings such as window shutters and wooden blind slats. Wooden slats and louvers are relatively high in strength and do not typically bend or sag or deform. Wooden window blind slats and other wood products such as frames and moldings are becoming quite expensive due to the increasing cost of wood and labor. There is a long felt need to find alternatives to wood that are lower in cost and easier to manufacture while retaining properties and characteristics of wood (e.g. weight/density, paintability and structural strength).
Wood substitutes are known. For example, U.S. Pat. No. 6,083,601 (Prince) discloses a Venetian blind slat formed of a dried wood byproduct (cellulose, or wood powders) and plastic. U.S. Pat. No. 6,583,189 (King) discloses articles, such as thermoplastic window covering products and window shutter components, containing a thermoplastic strengthened with dried diatomaceous earth.
Still, there is a continuing need to find new alternatives to wood that involve less plastic than conventional wood substitutes to reduce cost while retaining many of the benefits of the plastic material.